Line graphs, the mean and pie charts · Usually met around P6
Line graphs
Check the scale, then read each point.
How to do it
Method
Check the scale, then read each point
Thu 24°C, Fri 28°C: 28 − 24 = 4
Full working
28 − 24 = 4
In full
First see what each grid line on the side stands for, and where it starts (it isn't always 0). Find the point and read across to the axis. A line going up means an increase, and a line going down means a decrease. The steeper the line, the bigger the change. To find how much it rose, take the earlier point from the later one: Thursday 24°C, Friday 28°C, 28 − 24 = 4, so it rose by 4°C. For the highest minus the lowest, find the highest and lowest points, then take one from the other.
Worked examples
Have a go first, then open each one for the answer and the working.
Example 1
Savings in May = $?
Show the answer and working
Answer: Savings in May = $20
Each grid line stands for 10: May's point is on line 2, 2 × 10 = 20
Example 2
week 1 to week 2: grew by ? cm
Show the answer and working
Answer: week 1 to week 2: grew by 4 cm
Each grid line stands for 2: week 1's point is on line 1, 1 × 2 = 2; week 2's point is on line 3, 3 × 2 = 6; 6 − 2 = 4
Example 3
week 5 to week 6: grew by ? cm
Show the answer and working
Answer: week 5 to week 6: grew by 2 cm
Each grid line stands for 2: week 5's point is on line 1, 1 × 2 = 2; week 6's point is on line 2, 2 × 2 = 4; 4 − 2 = 2
Practise it in the game →Line graphs, the mean and pie charts · Free to start, unlimited questions, no download